v4.19.13 snapshot.
diff --git a/fs/cifs/export.c b/fs/cifs/export.c
new file mode 100644
index 0000000..ce8b7f6
--- /dev/null
+++ b/fs/cifs/export.c
@@ -0,0 +1,67 @@
+/*
+ * fs/cifs/export.c
+ *
+ * Copyright (C) International Business Machines Corp., 2007
+ * Author(s): Steve French (sfrench@us.ibm.com)
+ *
+ * Common Internet FileSystem (CIFS) client
+ *
+ * Operations related to support for exporting files via NFSD
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+ /*
+ * See Documentation/filesystems/nfs/Exporting
+ * and examples in fs/exportfs
+ *
+ * Since cifs is a network file system, an "fsid" must be included for
+ * any nfs exports file entries which refer to cifs paths. In addition
+ * the cifs mount must be mounted with the "serverino" option (ie use stable
+ * server inode numbers instead of locally generated temporary ones).
+ * Although cifs inodes do not use generation numbers (have generation number
+ * of zero) - the inode number alone should be good enough for simple cases
+ * in which users want to export cifs shares with NFS. The decode and encode
+ * could be improved by using a new routine which expects 64 bit inode numbers
+ * instead of the default 32 bit routines in fs/exportfs
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/exportfs.h>
+#include "cifsglob.h"
+#include "cifs_debug.h"
+#include "cifsfs.h"
+
+#ifdef CONFIG_CIFS_NFSD_EXPORT
+static struct dentry *cifs_get_parent(struct dentry *dentry)
+{
+ /* BB need to add code here eventually to enable export via NFSD */
+ cifs_dbg(FYI, "get parent for %p\n", dentry);
+ return ERR_PTR(-EACCES);
+}
+
+const struct export_operations cifs_export_ops = {
+ .get_parent = cifs_get_parent,
+/* Following five export operations are unneeded so far and can default:
+ .get_dentry =
+ .get_name =
+ .find_exported_dentry =
+ .decode_fh =
+ .encode_fs = */
+};
+
+#endif /* CONFIG_CIFS_NFSD_EXPORT */
+